.nullbox{
    width: 100%;
    height: 80px;
}
.main{
    width: 1160px;
    height: 500px;
    margin: 0 auto;
    border: 1px solid #000;
    ul{
        height: 25px;
        li{
            float: left;
            display: flex;
            justify-content: space-between;
            border: 1px solid #000;
            width: 100px;
            height: 100%;
            margin: 0 10px;
            text-align: center;
        }
    }
}

